A power peak regulation system and method based on supercritical CO2 integrated wind energy

Abstract

The present invention discloses an electric peak-shaving system and method based on supercritical CO2 integrated with wind energy utilization, which relates to the field of carbon emission reduction, including a CO2 production system, a CO2 compression system, and a thermoelectric generation system. The present invention heats up the CO2 produced by the respiration of microalgae at night and stores it as a working medium for supercritical CO2 power generation, and uses natural wind power to drive the stirring paddle of the microalgae culture tank and the piston of the gas compression unit respectively, thereby effectively utilizing wind energy. At the same time, the recycling of materials is realized, and the O2 produced by the photosynthesis of microalgae during the day can be used for respiration at night, while the CO2 produced at night can be used as a reactant for photosynthesis during the day. At the same time, the high-temperature and high-pressure CO2 gas of the CO2 storage tank is used to heat the exhaust steam at the turbine outlet, and the exhaust steam is secondary heated after heat exchange in the data center, so as to recover heat for heating and reduce heat loss.

Description

Technical Field

[0001] The invention relates to a power peak regulation system and method based on supercritical CO2 integrated wind energy utilization, belonging to the field of energy conservation, emission reduction and energy technology. Background Art

[0002] At present, supercritical CO2 power generation is a new utilization technology for controlling CO2 emissions. It uses supercritical CO2 as a working fluid to convert the energy of the heat source into mechanical energy. Due to the characteristics of high energy density and high heat transfer efficiency of supercritical carbon dioxide, the power generation system using it as a working fluid can achieve the efficiency of 700℃ of conventional steam Rankine cycle within a temperature range of 620℃, and is widely sought after by researchers from various countries.

[0003] From the perspective of adjusting the energy structure, new energy accounts for an increasingly larger proportion in the social energy structure, and renewable energy, especially solar energy, is of particular concern to people at present. The development direction of human use of solar energy also includes photosynthesis of plants (such as microalgae). Plant photosynthesis can fix a large amount of carbon dioxide. For example, the invention patent with application number 201810204218.7 discloses a cogeneration of heat and power using photosynthesis of microalgae. Compared with photosynthesis, the respiration of plants (such as microalgae) will produce a large amount of CO2. Controlling this part of CO2 emissions is also of great significance for carbon emission reduction. In addition, microalgae such as Chlorella can also be used to treat industrial wastewater and urban sewage in addition to improving the ecological environment. Wind is a natural phenomenon on the earth, which is caused by solar radiation heat. When the sun shines on the surface of the earth, the heat is different in different places on the surface of the earth, resulting in temperature differences, which causes convection movement of the atmosphere to form wind. Wind energy is the kinetic energy of air, and the size of wind energy depends on wind speed and air density. The utilization of renewable energy sources such as solar energy and wind energy is a hot research topic for scholars at home and abroad.

[0004] In addition, with the rapid development of the electronic information industry, the development of data centers is changing with each passing day. In particular, with the vigorous promotion of new infrastructure, the data center industry has ushered in a new peak of development. At present, while strengthening basic management, data centers need to cool down throughout the year to maintain a constant indoor temperature, which has brought huge power consumption and electricity bills. According to statistics, the energy consumption of refrigeration and air-conditioning equipment in the data center computer room accounts for about 40% of the total energy consumption, and the heat discharged by the data center has not been effectively utilized, which also causes great waste. Using the local environment to dissipate heat in the data center is a method that people are currently paying more attention to.

[0005] In view of this, the present invention proposes a power peak regulation system and method based on supercritical CO2 integrated wind energy utilization, which belongs to the field of energy conservation, emission reduction and energy technology. Summary of the invention

[0006] The purpose of the present invention is to overcome the shortcomings of the prior art and provide an electric peak-shaving system based on supercritical CO2 integrated with wind energy utilization, which can not only effectively utilize the heat generated by the data center and the CO2 generated by the respiration of microalgae, but also effectively utilize wind energy to compress CO2 and utilize high-temperature and high-pressure CO2 in multiple stages, thereby improving energy utilization efficiency.

[0007] The technical solution adopted by the present invention to solve the above problems is: an electric power peak-shaving system based on supercritical CO2 integrated wind energy utilization, characterized in that it includes a CO2 production system, a CO2 compression system and a thermoelectric generation system;

[0008] The CO2 production system comprises a microalgae culture tank, an O2 tank, a stirring paddle, and a first connecting shaft; the microalgae culture tank comprises a feed port, an O2 input port, a CO2 input port, and a gas output port, wherein the gas output port comprises three branches: an O2 output port, a first CO2 output port, and a second CO2 output port; the outlet of the O2 tank is connected to the O2 input port at the bottom of the microalgae culture tank, and the inlet of the O2 tank is connected to the O2 output port of the microalgae culture tank; the first CO2 output port of the microalgae culture tank is connected to the CO2 compression system, and the second CO2 output port is connected to the The stirring paddle is provided with an air inlet at the bottom of the microalgae culture tank, the O2 input port of the microalgae culture tank is connected to the air inlet at the bottom of the stirring paddle, the stirring paddle is composed of a plurality of stirring blades, and the stirring paddle is connected to the fan blades of the CO2 compression system through the first connecting shaft; the fan blades rotate under the action of natural wind, and the rotation of the stirring paddle is controlled by the first connecting shaft, thereby playing the role of stirring the microalgae liquid, making the CO2 diffuse more evenly, and the microalgae liquid can be in contact with the CO2 more fully and completely, thereby improving the overall quality of the microalgae liquid.

[0009] The CO2 compression system includes a fan blade, a main shaft, a gear box, a second connecting shaft, a low-temperature preheater, a gas compression unit, a medium-temperature preheater, and a CO2 storage tank; the fan blade is connected to the gear box through the main shaft, and the gear box is connected to the crank of the gas compression unit through the second connecting shaft; the gas compression unit is composed of a crank, a piston, a connecting rod, a compression chamber, an air inlet valve, and an air outlet valve, the crank is connected to the second connecting shaft, the cross-sectional area of ​​the output end of the second connecting shaft is consistent with the cross-sectional area of ​​the crank, and an integrated design is performed, the crank is connected to the piston through a connecting rod, the first connecting shaft and the main shaft are on the same center line, and the The center line of the second connecting shaft is kept horizontal with the center lines of the first connecting shaft and the main shaft; the inlet channel where the air intake valve is located is connected to the CO2 first output port of the microalgae culture tank through a low-temperature preheater, and the air outlet valve of the gas compression unit is connected to the CO2 storage tank through a medium-temperature preheater; the gas outlet of the CO2 storage tank is divided into two branches, of which the first branch is connected to the turbine of the thermoelectric generation system, and the second branch is connected to the high-temperature regenerator of the thermoelectric generation system; under the action of natural wind force, the fan blades drive the gear box to rotate through the main shaft, the gear box speed increase drives the crank to rotate through the second connecting shaft, and the crank drives the piston to move up and down through the connecting rod.

[0010] The thermoelectric generating system includes a turbine, a generator, an industrial user, a data center, a high-temperature regenerator, a low-temperature regenerator, a heating user, and a precooler; the turbine includes two input ports and two output ports, wherein the first input port is connected to the first branch of the CO2 storage tank output port, and the second input port is connected to the output port from the data center; the first output port is an industrial steam extraction outlet connected to the industrial user through an industrial steam pipeline, and the second output port is connected to the high-temperature regenerator; the turbine is coaxially connected to the generator; the high-temperature regenerator includes two gas input ports and two gas output ports, wherein the first gas input port is connected to the second branch of the CO2 storage tank gas outlet, and the second gas input port is connected to the second output port of the turbine. The first gas output port is connected to the data center, and the second gas output port is connected to the low-temperature regenerator; the gas input port of the data center is connected to the first gas output port of the high-temperature regenerator, and the gas output port of the data center is divided into two branches, the first branch is connected to the second input port of the turbine, and the second branch is connected to the low-temperature regenerator; the low-temperature regenerator includes two input ports and two output ports, wherein the first input port is connected to the second branch of the data center, the second input port is connected to the high-temperature regenerator, the first output port is connected to the high-temperature regenerator after merging with the second branch of the CO2 storage tank outlet, and the second output port is connected to the precooler through the heating user, and the output port of the precooler is connected to the air inlet valve of the gas compression unit.

[0011] When the microalgae respire at night, the O2 in the O2 tank enters the microalgae culture tank along the O2 input port at the bottom of the microalgae culture tank and through the air inlet at the bottom of the stirring paddle. The CO2 generated by the respiration of the microalgae enters the CO2 compression system through the first CO2 output port in one way, and enters the bottom of the microalgae culture tank through the second CO2 output port in another way, as a reactant for the photosynthesis of the microalgae during the day. During the day, the microalgae perform photosynthesis, inhale CO2, and the generated O2 enters the O2 tank through the O2 output port of the microalgae culture tank. The stirring paddle is connected to the fan blades through the first connecting shaft, and the fan blades rotate under the action of natural wind to control the rotation of the stirring paddle, thereby stirring the microalgae liquid.

[0012] A four-way valve is provided at the junction of the branch of the gas output port of the microalgae culture tank. At night, the O2 output port is closed, the CO2 first output port is opened, and the CO2 second output port is closed. During the day, the O2 output port is opened and the CO2 second output port is opened.

[0013] A power peak-shaving method based on supercritical CO2 integrated wind energy utilization, including the power peak-shaving system, the power peak-shaving method includes the following steps: the fan blades rotate under the action of natural wind force, through the main shaft, under the speed-increasing action of the gear box, drive the second connecting shaft to rotate, and then drive the crank of the gas compression unit to rotate, the crank rotation drives the piston to move up and down through the connecting rod, the crank rotates one circle, the piston reciprocates up and down for two strokes, and completes a working cycle, and a working cycle refers to the gas compression unit completing a work process of intake, compression, and air delivery; the piston moves from the top dead center to the bottom dead center, at this During the process, the air inlet valve of the gas compression unit is opened and the air outlet valve is closed. After the CO2 of the first branch of the CO2 output port of the microalgae culture tank enters the low-temperature preheater, the low-temperature and low-pressure CO2 enters the compression chamber through the air inlet valve to complete the air intake process; the piston moves upward from the lower dead center to compress the CO2. At this time, the air inlet valve and the air outlet valve are both closed. When the pressure and temperature of CO2 reach 20MPa and 450°C, the air outlet valve is opened, and supercritical CO2 enters the thermoelectric generation system. The piston reaches the upper dead center, and the air outlet valve is closed to complete the compression and air delivery process. The gas compression unit completes a working cycle.

[0014] The 20MPa, 450℃ CO2 passes through the outlet valve of the gas compression unit, is preheated by the medium-temperature preheater, and enters the CO2 storage tank. The gas outlet of the CO2 storage tank is divided into two branches, the first branch is connected to the turbine, and the second branch is connected to the high-temperature regenerator; the 10MPa, 200℃ intermediate industrial exhaust gas is supplied to industrial users through the first output port of the turbine, and the exhaust gas from the second output port of the turbine enters the second gas input port of the high-temperature regenerator to exchange heat with the 20Mpa, 500℃ CO2 from the bottom outlet of the CO2 storage tank, and the exhaust gas enters the low-temperature regenerator through the second gas output port of the high-temperature regenerator. The CO2 after releasing heat enters the data center through the first gas output port of the high-temperature regenerator. The CO2 after absorbing the heat of the data center is divided into two bypasses, one of which merges with the first branch of the CO2 storage tank to enter the turbine to do work, and the other bypass is connected to the first input port of the low-temperature regenerator to exchange heat with the exhaust gas from the second gas output port of the high-temperature regenerator. On the one hand, the cooled CO2 merges with the gas from the second branch of the CO2 storage tank to enter the high-temperature regenerator. On the other hand, the heated exhaust gas of 5Mpa and 350℃ first provides heat to the user and then enters the precooler. The precooled CO2 enters the air inlet valve of the gas compression unit.

[0015] The pressure and temperature of the CO2 storage tank are 20 MPa and 500°C, and the intermediate exhaust temperature and pressure are 10 MPa and 200°C.

[0016] Compared with the prior art, the present invention has the following advantages and effects:

[0017] The present invention preheats, compresses and stores the CO2 produced by the respiration of microalgae at night, and uses it as a working fluid for supercritical CO2 power generation during the day to alleviate the peak electricity consumption. At the same time, natural wind energy is used to drive the stirring paddle on the one hand to mix the microalgae liquid and the gas evenly, and on the other hand, the gas compression unit is driven by the gear box to compress the CO2, effectively utilizing wind energy.

[0018] The present invention realizes the recycling of materials. The O2 produced by the photosynthesis of microalgae during the day can be used for breathing at night, and the CO2 produced at night can be used as a reactant for photosynthesis during the day. The high-temperature and high-pressure CO2 at the outlet of the CO2 storage tank with a temperature of 20Mpa and 500°C is used to heat the exhaust steam at the turbine outlet. At the same time, the heat generated by the data center is used to cool the data center on the one hand, and to heat the low-temperature CO2 on the other hand. At the same time, the CO2 at the outlet of the data center with a temperature of 20Mpa and 500°C is used to heat the exhaust steam after heating, realizing the cascade utilization of waste heat. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic structural diagram of an embodiment of the present invention.

[0020] Figure 2 It is a schematic diagram of the CO2 production system.

[0021] Figure 3 It is a structural schematic diagram of a comparative example of the present invention.

[0022] 1. Microalgae culture tank; 2. O2 tank; 3. Stirring paddle; 4. First connecting shaft; 5. Fan blades; 6. Main shaft; 7. Gear box; 8. Second connecting shaft; 9. Low-temperature preheater; 10. Gas compression unit; 101. Crank; 102. Piston; 103. Connecting rod; 104. Compression chamber; 105. Inlet valve; 106. Exit valve; 11. Medium-temperature preheater; 12. CO2 storage tank; 13. Turbine; 14. Generator; 15. Industrial user; 16. Data center; 17. High-temperature regenerator; 18. Low-temperature regenerator; 19. Heating user; 20. Precooler. DETAILED DESCRIPTION

[0023] The present invention will be further described in detail below with reference to the accompanying drawings and by way of examples. The following examples are intended to explain the present invention but the present invention is not limited to the following examples.

[0024] Example

[0025] The technical solution adopted by the present invention to solve the above problems is: an electric power peak-shaving system based on supercritical CO2 integrated wind energy utilization, characterized in that it includes a CO2 production system, a CO2 compression system and a thermoelectric generation system;

[0026] The CO2 production system comprises a microalgae culture tank 1, an O2 tank 2, a stirring paddle 3, and a first connecting shaft 4; the microalgae culture tank 1 comprises a feed port, an O2 input port, a CO2 input port, and a gas output port, wherein the gas output port comprises three branches: an O2 output port, a first CO2 output port, and a second CO2 output port; the outlet of the O2 tank 2 is connected to the O2 input port at the bottom of the microalgae culture tank 1, and the inlet of the O2 tank 2 is connected to the O2 output port of the microalgae culture tank 1; the first CO2 output port of the microalgae culture tank 1 is connected to the gas compression system, and the second CO2 output port is connected to the gas compression system. The stirring paddle 3 is provided with an air inlet at the bottom, the O2 input port of the microalgae culture tank 1 is connected to the air inlet at the bottom of the stirring paddle 3, the stirring paddle 3 is composed of a plurality of stirring blades, and the stirring paddle 3 is connected to the fan blade 5 of the CO2 compression system through the first connecting shaft 4; the fan blade 5 rotates under the action of natural wind, and the rotation of the stirring paddle 3 is controlled by the first connecting shaft 4, so as to play the role of stirring the microalgae liquid, so that the CO2 diffusion is more uniform, and the microalgae liquid can be in contact with the CO2 more fully and completely, thereby improving the overall quality of the microalgae liquid.

[0027] The CO2 compression system includes a fan blade 5, a main shaft 6, a gear box 7, a second connecting shaft 8, a low-temperature preheater 9, a gas compression unit 10, a medium-temperature preheater 11, and a CO2 storage tank 12; the fan blade 5 is connected to the gear box 7 through the main shaft 6, and the gear box 7 is connected to the crank 101 of the gas compression unit 10 through the second connecting shaft 8; the gas compression unit 10 is composed of a crank 101, a piston 102, a connecting rod 103, a compression chamber 104, an inlet valve 105, and an outlet valve 106, the crank 101 is connected to the second connecting shaft 8, the cross-sectional area of ​​the output end of the second connecting shaft 8 is consistent with the cross-sectional area of ​​the crank 101, and an integrated design is performed, the crank 101 is connected to the piston 102 through the connecting rod 103, and the first connecting shaft 4. The main shaft 6 is on the same center line, and the center line of the second connecting shaft 8 is kept horizontal with the center lines of the first connecting shaft 4 and the main shaft 6; the inlet channel where the air intake valve 105 is located is connected to the CO2 first output port of the microalgae culture tank 1 through the low-temperature preheater 9, and the air outlet valve 106 of the gas compression unit 10 is connected to the CO2 storage tank 12 through the medium-temperature preheater 11; the gas outlet of the CO2 storage tank 12 is divided into two branches, of which the first branch is connected to the turbine 13, and the second branch is connected to the high-temperature regenerator 17; under the action of natural wind force, the fan blades 5 drive the gear box 7 to rotate through the main shaft 6, and the gear box 7 speeds up and drives the crank 101 to rotate through the second connecting shaft 8, and the crank 101 drives the piston 102 to move up and down through the connecting rod 103.

[0028] The thermoelectric generating system includes a turbine 13, a generator 14, an industrial user 15, a data center 16, a high-temperature regenerator 17, a low-temperature regenerator 18, a heating user 19, and a precooler 20;

[0029] The turbine 13 includes two input ports and two output ports, wherein the first input port is connected to the first branch of the output port of the CO2 storage tank 12, and the second input port is connected to the output port from the data center 16; the first output port is an industrial steam extraction outlet connected to the industrial user 15 through an industrial steam pipeline, and the second output port is connected to a high-temperature regenerator 17; the turbine 13 is coaxially connected to the generator 14;

[0030] The high-temperature regenerator 17 includes two gas input ports and two gas output ports, wherein the first gas input port is connected to the second branch of the gas outlet of the CO2 storage tank 12, the second gas input port is connected to the second output port of the turbine 13, the first gas output port is connected to the data center 16, and the second gas output port is connected to the low-temperature regenerator 18; the gas input port of the data center 16 is connected to the first gas output port of the high-temperature regenerator 17, and the gas output port of the data center 16 is divided into two branches, the first branch is connected to the second input port of the turbine 13, and the second branch is connected to the low-temperature regenerator 18; the low-temperature regenerator 18 includes two input ports and two output ports, wherein the first input port is connected to the second branch of the data center 16, the second input port is connected to the high-temperature regenerator 17, the first output port is connected to the high-temperature regenerator 18 after merging with the second branch of the outlet of the CO2 storage tank 12, and the second output port is connected to the precooler 20 through the heating user 19, and the output port of the precooler 20 is connected to the air inlet valve 105 of the gas compression unit 10.

[0031] The working method of the power peak load regulation system based on supercritical CO2 integrated wind energy utilization is divided into three processes according to gas flow, as follows:

[0032] When the microalgae breathe at night, the O2 in the O2 tank 2 enters the microalgae culture tank 1 along the O2 input port at the bottom of the microalgae culture tank 1 and through the air inlet at the bottom of the stirring paddle 3. The CO2 generated by the respiration of the microalgae enters the CO2 compression system through the first CO2 output port and enters the bottom of the microalgae culture tank 1 through the second CO2 output port as a reactant for the photosynthesis of the microalgae during the day. During the day, the microalgae perform photosynthesis, inhale CO2, and the generated O2 enters the O2 tank 2 through the O2 output port of the microalgae culture tank 1. The stirring paddle 3 is connected to the fan blade 5 through the first connecting shaft 4. The fan blade 5 rotates under the action of natural wind force, controlling the rotation of the stirring paddle 3, thereby playing the role of stirring the microalgae liquid, so that CO2 and O2 diffuse more evenly, and the microalgae liquid can react more fully and completely with CO2 and O2, and respiration and photosynthesis can occur more fully.

[0033] A four-way valve is provided at the junction of the branch of the gas outlet of the microalgae culture tank 1. At night, the O2 outlet is closed, the first CO2 outlet is opened, and the second CO2 outlet is closed. During the day, the O2 outlet is opened and the second CO2 outlet is opened.

[0034] 2.CO2 compression process

[0035] The fan blades 5 rotate under the action of natural wind force, and through the main shaft 6, under the action of the gear box 7 to increase the speed, drive the second connecting shaft 8 to rotate, and then drive the crank 101 of the gas compression unit 10 to rotate. The rotation of the crank 101 drives the piston 102 to move up and down through the connecting rod 103. Every time the crankshaft 101 rotates one turn, the piston 102 reciprocates up and down for two strokes to complete a working cycle. One working cycle refers to the gas compression unit 10 completing a working process of intake, compression, and air delivery. The piston 102 moves from the top dead center to the bottom dead center. During this process, the intake valve 105 of the gas compression unit 10 is opened and the outlet valve 106 is closed. After the CO2 of the first branch of the CO2 output port of the microalgae culture tank 1 enters the low-temperature preheater 9, the low-temperature and low-pressure CO2 enters the inner cavity of the gas compression unit 10 through the intake valve 105, completing the intake process; the piston 102 moves upward from the bottom dead center to compress the CO2. At this time, the intake valve 105 and the outlet valve 106 are both closed. When the pressure and temperature of CO2 reach 20MPa and 450°C (at this time, the piston 102 has not reached the top dead center), the outlet valve 106 is opened, and the supercritical CO2 enters the thermoelectric generation system. The piston 102 reaches the top dead center, and the outlet valve 106 is closed, completing the compression and gas delivery process; in this way, the gas compression unit 10 completes a working cycle.

[0036] 3. Thermoelectric generation process:

[0037] The CO2 at 20MPa and 450℃ passes through the outlet valve 106 of the gas compression unit 10, is preheated by the medium-temperature preheater 11, and enters the CO2 storage tank 12. The gas outlet of the CO2 storage tank 12 is divided into two branches, the first branch is connected to the turbine 13, and the second branch is connected to the high-temperature regenerator 17;

[0038] The intermediate industrial exhaust gas (10MPa, 200°C) is supplied to the industrial user 15 through the first outlet of the turbine 13.

[0039] The exhaust gas from the second outlet of the turbine 13 enters the second gas inlet of the high-temperature regenerator 17 and exchanges heat with the CO2 (20Mpa, 500°C) from the bottom outlet of the CO2 storage tank 12.

[0040] The exhaust gas enters the low-temperature regenerator 18 through the second gas outlet of the high-temperature regenerator 17.

[0041] The CO2 after releasing heat enters the data center 16 through the first gas outlet of the high-temperature regenerator 17. The CO2 after absorbing the heat of the data center 16 is divided into two bypasses, one of which merges with the first branch of the CO2 storage tank 12 to enter the turbine 13 to do work, and the other bypass is connected to the first input port of the low-temperature regenerator 18 to exchange heat with the exhaust gas from the second gas outlet of the high-temperature regenerator 17. On the one hand, the CO2 after cooling merges with the gas of the second branch of the CO2 storage tank 12 to enter the high-temperature regenerator 17, and on the other hand, the exhaust gas after heating (5Mpa, 350°C) first provides heat to the user 19, and then enters the precooler 20. The precooled CO2 enters the air inlet valve 105 of the gas compression unit 10;

[0042] Furthermore, the pressure and temperature of the CO2 storage tank 12 of the system of the present invention is 20 MPa and 500°C, and the intermediate exhaust temperature and pressure is 10 MPa and 200°C.

[0043] Furthermore, the pressure and temperature of the CO2 storage tank 12 of the system of the present invention is 20 MPa and 500°C, and the intermediate exhaust temperature and pressure are 10 MPa and 200°C.

[0044] Furthermore, at night, the outlet valve 106 of the gas compression unit 10 is opened, and the CO2 produced by the microalgae culture tank 1 enters the CO2 compression system, becomes high-temperature and high-pressure CO2 and enters the thermoelectric generation system; during the day, the outlet valve 106 of the gas compression unit 10 is closed, and the system uses the high-temperature and high-pressure CO2 in the CO2 storage tank 12 to generate electricity and heat.

[0045] Comparative example.

[0046] The technical solution adopted by the present invention to solve the above problems is: an electric power peak-shaving system based on supercritical CO2 integrated wind energy utilization, characterized in that it includes a CO2 production system, a CO2 compression system and a thermoelectric generation system;

[0047] The CO2 production system comprises a microalgae culture tank 1, an O2 tank 2, a stirring paddle 3, and a first connecting shaft 4; the microalgae culture tank 1 comprises a feed port, an O2 input port, a CO2 input port, and a gas output port, wherein the gas output port comprises three branches: an O2 output port, a first CO2 output port, and a second CO2 output port; the outlet of the O2 tank 2 is connected to the O2 input port at the bottom of the microalgae culture tank 1, and the inlet of the O2 tank 2 is connected to the O2 output port of the microalgae culture tank 1; the first CO2 output port of the microalgae culture tank 1 is connected to the gas compression system, and the second CO2 output port is connected to the gas compression system. The stirring paddle 3 is provided with an air inlet at the bottom, the O2 input port of the microalgae culture tank 1 is connected to the air inlet at the bottom of the stirring paddle 3, the stirring paddle 3 is composed of a plurality of stirring blades, and the stirring paddle 3 is connected to the fan blade 5 of the CO2 compression system through the first connecting shaft 4; the fan blade 5 rotates under the action of natural wind, and the rotation of the stirring paddle 3 is controlled by the first connecting shaft 4, so as to play the role of stirring the microalgae liquid, so that the CO2 diffusion is more uniform, and the microalgae liquid can be in contact with the CO2 more fully and completely, thereby improving the overall quality of the microalgae liquid.

[0048] The CO2 compression system includes a fan blade 5, a main shaft 6, a gear box 7, a second connecting shaft 8, a low-temperature preheater 9, a gas compression unit 10, a medium-temperature preheater 11, and a CO2 storage tank 12; the fan blade 5 is connected to the gear box 7 through the main shaft 6, and the gear box 7 is connected to the crank 101 of the gas compression unit 10 through the second connecting shaft 8; the gas compression unit 10 is composed of a crank 101, a piston 102, a connecting rod 103, a compression chamber 104, an inlet valve 105, and an outlet valve 106. The crank 101 is connected to the second connecting shaft 8, and the cross-sectional area of ​​the output end of the second connecting shaft 8 is consistent with the cross-sectional area of ​​the crank 101, and an integrated design is performed. The crank 101 is connected to the piston through the connecting rod 103. 102 is connected, the first connecting shaft 4 and the main shaft 6 are on the same center line, and the center line of the second connecting shaft 8 is kept horizontal with the center lines of the first connecting shaft 4 and the main shaft 6; the inlet channel where the air intake valve 105 is located is connected to the CO2 first output port of the microalgae culture tank 1 through the low-temperature preheater 9, and the air outlet valve 106 of the gas compression unit 10 is connected to the CO2 storage tank 12 through the medium-temperature preheater 11; the gas outlet of the CO2 storage tank 12 is connected to the turbine 13; under the action of natural wind force, the fan blades 5 drive the gear box 7 to rotate through the main shaft 6, the gear box 7 speed increases and drives the crank 101 to rotate through the second connecting shaft 8, and the crank 101 drives the piston 102 to move up and down through the connecting rod 103.

[0049] The thermoelectric generating system includes a turbine 13, a generator 14, an industrial user 15, a heating user 19, and a precooler 20; the turbine 13 is connected to the gas output port of the CO2 storage tank 12, the first output port is an industrial steam extraction outlet connected to the industrial user 15 through an industrial steam pipeline, and the second output port is connected to the heating user 19 and connected to the precooler 20; the turbine 13 is coaxially connected to the generator 14, and the output port of the precooler 20 is connected to the air inlet valve 105 of the gas compression unit 10.

[0050] The working method of the power peak load regulation system based on supercritical CO2 integrated wind energy utilization is divided into three processes according to gas flow, as follows:

[0051] When the microalgae breathe at night, the O2 in the O2 tank 2 enters the microalgae culture tank 1 along the O2 input port at the bottom of the microalgae culture tank 1 and through the air inlet at the bottom of the stirring paddle 3. The CO2 generated by the respiration of the microalgae enters the CO2 compression system through the first CO2 output port and enters the bottom of the microalgae culture tank 1 through the second CO2 output port as a reactant for the photosynthesis of the microalgae during the day. During the day, the microalgae perform photosynthesis, inhale CO2, and the generated O2 enters the O2 tank 2 through the O2 output port of the microalgae culture tank 1. The stirring paddle 3 is connected to the fan blade 5 through the first connecting shaft 4. The fan blade 5 rotates under the action of natural wind force, controlling the rotation of the stirring paddle 3, thereby playing the role of stirring the microalgae liquid, so that CO2 and O2 diffuse more evenly, and the microalgae liquid can react more fully and completely with CO2 and O2, and respiration and photosynthesis can occur more fully.

[0052] A four-way valve is provided at the junction of the branch of the gas outlet of the microalgae culture tank 1. At night, the O2 outlet is closed, the first CO2 outlet is opened, and the second CO2 outlet is closed. During the day, the O2 outlet is opened and the second CO2 outlet is opened.

[0053] 2.CO2 compression process

[0054] The fan blades 5 rotate under the action of natural wind force, and through the main shaft 6, under the action of the gear box 7 to increase the speed, drive the second connecting shaft 8 to rotate, and then drive the crank 101 of the gas compression unit 10 to rotate. The rotation of the crank 101 drives the piston 102 to move up and down through the connecting rod 103. Every time the crankshaft 101 rotates one turn, the piston 102 reciprocates up and down for two strokes to complete a working cycle. One working cycle refers to the gas compression unit 10 completing a working process of intake, compression, and air delivery. The piston 102 moves from the top dead center to the bottom dead center. During this process, the intake valve 105 of the gas compression unit 10 is opened and the outlet valve 106 is closed. After the CO2 of the first branch of the CO2 output port of the microalgae culture tank 1 enters the low-temperature preheater 9, the low-temperature and low-pressure CO2 enters the inner cavity of the gas compression unit 10 through the intake valve 105, completing the intake process; the piston 102 moves upward from the bottom dead center to compress the CO2. At this time, the intake valve 105 and the outlet valve 106 are both closed. When the pressure and temperature of CO2 reach 20MPa and 450°C (at this time, the piston 102 has not reached the top dead center), the outlet valve 106 is opened, and the supercritical CO2 enters the thermoelectric generation system. The piston 102 reaches the top dead center, and the outlet valve 106 is closed, completing the compression and gas delivery process; in this way, the gas compression unit 10 completes a working cycle.

[0055] 3. Thermoelectric generation process:

[0056] The CO2 at 20MPa and 450℃ passes through the outlet valve 106 of the gas compression unit 10, is preheated by the medium-temperature preheater 11, and enters the CO2 storage tank 12. The gas outlet of the CO2 storage tank 12 is connected to the turbine 13. The intermediate industrial exhaust gas (10MPa, 200℃) is supplied to the industrial user 19 through the first output port of the turbine 13. The exhaust gas from the second output port of the turbine 13 provides heat for the user and is connected to the precooler 20. The precooled CO2 enters the CO2 compression system through the inlet valve 105 of the gas compression unit 10.

[0057] Compared with the embodiment, the comparative example lacks the data center 16, the high-temperature regenerator 17, and the low-temperature regenerator 18.

[0058] The above-mentioned embodiments and comparative examples were simulated and calculated, and the ambient pressure and temperature were 22°C and 0.10MPa respectively. All simulations assume that the microalgae breathe normally at night, the wind speed is assumed to be 7m / s, the CO2 flow rate output by the CO2 storage tank 12 is 20kg / s, and the ratio of the CO2 storage tank 12 entering the turbine 13 and the high-temperature regenerator 17 in the embodiment is 1:9; the turbine outlet temperature and pressure are 150°C and 5MPa, and the intermediate exhaust accounts for 1 / 10; the gearbox is a two-stage planetary and one-stage parallel shaft structure, and the transmission ratio is about 90. The simulation parameter settings are shown in Table 1.

[0059] Table 1 Basic cycle parameters of the system

[0060]

[0061]

[0062] In order to comprehensively and reasonably evaluate the system performance, the system modeling of the embodiment and the comparative example was conducted to conduct a thermodynamic efficiency analysis. The system cycle efficiency of the embodiment reached 57%, while that of the comparative example was only 42%.

[0063] The fundamental reason why the efficiency of the example system is significantly improved is that first, the high-temperature and high-pressure CO2 gas in the CO2 storage tank is used to heat the exhaust steam at the turbine outlet, and the exhaust steam is reheated after heat exchange in the data center to recover heat for heating and reduce heat loss.

[0064] In addition, the present invention heats up the CO2 produced by the night respiration of the microalgae and stores it as a working medium for supercritical CO2 power generation, and uses natural wind power to drive the stirring blade of the microalgae culture tank and the piston of the gas compression unit, respectively, effectively utilizing wind energy. At the same time, the recycling of materials is achieved, and the O2 produced by the photosynthesis of the microalgae during the day can be used for respiration at night, and the CO2 produced at night can be used as a reactant for photosynthesis during the day.

[0065] In summary, the power peak-shaving system based on supercritical CO2 integrated wind energy utilization in the present invention has good system thermal performance and economic benefits, and has obvious energy-saving effects.

[0066] The contents not described in detail in this specification belong to the prior art known to the professional and technical personnel in this field. Although the present invention has been disclosed as above by the embodiments, it is not intended to limit the protection scope of the present invention. Any changes and modifications made by any technician familiar with the technology without departing from the concept and scope of the present invention shall belong to the protection scope of the present invention.

Claims

1. A power peak load regulation system based on supercritical CO2 integrated wind energy utilization, characterized in that: Including CO2 production system, CO2 compression system and thermal power generation system; The CO2 production system comprises a microalgae culture tank, an O2 tank, a stirring paddle, and a first connecting shaft; the microalgae culture tank comprises a feed port, an O2 input port, a CO2 input port, and a gas output port, wherein the gas output port comprises three branches: an O2 output port, a CO2 first output port, and a CO2 second output port, wherein the outlet of the O2 tank is connected to the O2 input port at the bottom of the microalgae culture tank, and the inlet of the O2 tank is connected to the O2 output port of the microalgae culture tank; the CO2 first output port of the microalgae culture tank is connected to the CO2 compression system, and the CO2 second output port is connected to the CO2 input port at the bottom of the microalgae culture tank; the stirring paddle has an air inlet at the bottom, the O2 input port of the microalgae culture tank is connected to the air inlet at the bottom of the stirring paddle, the stirring paddle is composed of a plurality of stirring paddle blades, and the stirring paddle is connected to the fan blades of the CO2 compression system through the first connecting shaft; the fan blades rotate under the action of natural wind, and the stirring paddle is controlled to rotate through the first connecting shaft, thereby stirring the microalgae liquid; The CO2 compression system includes a fan blade, a main shaft, a gear box, a second connecting shaft, a low-temperature preheater, a gas compression unit, a medium-temperature preheater, and a CO2 storage tank; the fan blade is connected to the gear box through the main shaft, and the gear box is connected to the crank of the gas compression unit through the second connecting shaft; the gas compression unit is composed of a crank, a piston, a connecting rod, a compression chamber, an air inlet valve, and an air outlet valve, the crank is connected to the second connecting shaft, the cross-sectional area of ​​the output end of the second connecting shaft is consistent with the cross-sectional area of ​​the crank, and an integrated design is performed, the crank is connected to the piston through the connecting rod, the first connecting shaft and the main shaft are on the same center line, and the center line of the second connecting shaft is The center lines of the first connecting shaft and the main shaft are kept horizontal; the inlet channel where the air intake valve is located is connected to the first CO2 output port of the microalgae culture tank through the low-temperature preheater, and the air outlet valve of the gas compression unit is connected to the CO2 storage tank through the medium-temperature preheater; the gas outlet of the CO2 storage tank is divided into two branches, wherein the first branch is connected to the turbine of the thermoelectric generation system, and the second branch is connected to the high-temperature regenerator of the thermoelectric generation system; the fan blades of the fan drive the gear box to rotate through the main shaft under the action of natural wind force, and the gear box speed increases and drives the crank to rotate through the second connecting shaft, and the crank drives the piston to move up and down through the connecting rod; The thermoelectric generating system includes a turbine, a generator, an industrial user, a data center, a high-temperature regenerator, a low-temperature regenerator, a heating user, and a precooler; the turbine includes two input ports and two output ports, wherein the first input port is connected to the first branch of the CO2 storage tank output port, and the second input port is connected to the output port of the data center; the first output port is an industrial steam extraction outlet, which is connected to the industrial user through an industrial steam pipeline, and the second output port is connected to the high-temperature regenerator; the turbine is coaxially connected to the generator; the high-temperature regenerator includes two gas input ports and two gas output ports, wherein the first gas input port is connected to the second branch of the CO2 storage tank gas outlet, and the second gas input port is connected to the second output port of the turbine, and the first The gas output port is connected to the data center, and the second gas output port is connected to the low-temperature regenerator; the gas input port of the data center is connected to the first gas output port of the high-temperature regenerator, and the gas output port of the data center is divided into two branches, the first branch is connected to the second input port of the turbine, and the second branch is connected to the low-temperature regenerator; the low-temperature regenerator includes two input ports and two output ports, wherein the first input port is connected to the second branch of the data center, the second input port is connected to the high-temperature regenerator, the first output port is connected to the high-temperature regenerator after merging with the second branch of the CO2 storage tank outlet, the second output port is connected to the precooler through the heating user, and the output port of the precooler is connected to the air inlet valve of the gas compression unit.

2. The power peak load regulation system based on supercritical CO2 integrated wind energy utilization according to claim 1 is characterized in that: When the microalgae respire at night, the O2 in the O2 tank enters the microalgae culture tank along the O2 input port at the bottom of the microalgae culture tank and through the air inlet at the bottom of the stirring paddle. The CO2 generated by the respiration of the microalgae enters the CO2 compression system through the first CO2 output port in one way, and enters the bottom of the microalgae culture tank through the second CO2 output port in another way, as a reactant for the photosynthesis of the microalgae during the day. During the day, the microalgae perform photosynthesis, inhale CO2, and the generated O2 enters the O2 tank through the O2 output port of the microalgae culture tank. The stirring paddle is connected to the fan blades through the first connecting shaft, and the fan blades rotate under the action of natural wind to control the rotation of the stirring paddle, thereby stirring the microalgae liquid.

3. The power peak load regulation system based on supercritical CO2 integrated wind energy utilization according to claim 2 is characterized in that: A four-way valve is provided at the junction of the branch of the gas output port of the microalgae culture tank. At night, the O2 output port is closed, the CO2 first output port is opened, and the CO2 second output port is closed. During the day, the O2 output port is opened and the CO2 second output port is opened.

4. A method for peak load regulation of electricity based on supercritical CO2 integrated wind energy utilization, characterized in that: The power peak-shaving system comprises the following steps: the fan blades rotate under the action of natural wind force, and through the main shaft, under the action of the speed increasing function of the gear box, the second connecting shaft is driven to rotate, thereby driving the crank of the gas compression unit to rotate, and the crank rotation drives the piston to move up and down through the connecting rod. The crank rotates one circle, and the piston reciprocates up and down for two strokes to complete a working cycle. A working cycle refers to the working process of the gas compression unit completing one intake, compression, and air delivery; the piston moves from the top dead center to the bottom dead center, and during this process the gas The air inlet valve of the compression unit is opened and the air outlet valve is closed. After the CO2 of the first branch of the CO2 output port of the microalgae culture tank enters the low-temperature preheater, the low-temperature and low-pressure CO2 enters the compression chamber through the air inlet valve to complete the air intake process; the piston moves upward from the lower dead center to compress the CO2. At this time, the air inlet valve and the air outlet valve are both closed. When the pressure and temperature of CO2 reach 20MPa and 450°C, the air outlet valve is opened, and supercritical CO2 enters the thermoelectric generation system. The piston reaches the upper dead center, and the air outlet valve is closed to complete the compression and air delivery process. The gas compression unit completes a working cycle.

5. The power peak regulation method based on supercritical CO2 integrated wind energy utilization according to claim 4 is characterized in that: The 20MPa, 450℃ CO2 passes through the outlet valve of the gas compression unit, is preheated by the medium-temperature preheater, and enters the CO2 storage tank. The gas outlet of the CO2 storage tank is divided into two branches, the first branch is connected to the turbine, and the second branch is connected to the high-temperature regenerator; the 10MPa, 200℃ intermediate industrial exhaust gas is supplied to industrial users through the first output port of the turbine, and the exhaust gas from the second output port of the turbine enters the second gas input port of the high-temperature regenerator to exchange heat with the 20Mpa, 500℃ CO2 from the bottom outlet of the CO2 storage tank, and the exhaust gas enters the low-temperature regenerator through the second gas output port of the high-temperature regenerator. The CO2 after releasing heat enters the data center through the first gas output port of the high-temperature regenerator. The CO2 after absorbing the heat of the data center is divided into two bypasses, one of which merges with the first branch of the CO2 storage tank to enter the turbine to do work, and the other bypass is connected to the first input port of the low-temperature regenerator to exchange heat with the exhaust gas from the second gas output port of the high-temperature regenerator. On the one hand, the cooled CO2 merges with the gas from the second branch of the CO2 storage tank to enter the high-temperature regenerator. On the other hand, the heated exhaust gas of 5Mpa and 350℃ first provides heat to the user and then enters the precooler. The precooled CO2 enters the air inlet valve of the gas compression unit.

6. The method for peak load regulation of electricity based on supercritical CO2 integrated wind energy utilization according to claim 5 is characterized in that: The pressure and temperature of the CO2 storage tank are 20 MPa and 500°C, and the intermediate exhaust temperature and pressure are 10 MPa and 200°C.

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